Heating apparatus



Nov. 23, 1943. w, s LANDON' 2,335,212

HEATING APPARATUS Filiaal Dc. 11, 1939 2 Sheets-Sheet 1 Fra-l INVENTOR M ATTORNEY NOV 23, i943- w. LANDON HEATING APPARATUS Filed Dc. ll, 1939 2 Sheets-Shee'; 2

. lNvENToR www, /J Ma/ow /lf gli-wu.,

. FIG-2 ATTORNEY Patented Nov. 23, 1943 HEATING APPARATUS Walter S. Landon, Detroit, Mich., assignor to Detroit Lubrlcator Company, Detroit, Mich., a corporation of Michigan Application December 11, 1939, serial No. 308,583

24 Claims.

This invention relates generally to heating apl paratus and' more specifically to th'e modulating type of apparatus which is applicable among other uses to control the ow of liquid fuel to an hydroxylation type burner.

An object of the invention is to provide means for controlling a heating apparatus in accordance with variations in temperature of the heated medium.

Another object is to provide a new and novel means for controlling an oil burner whereby its Output is varied in' steps.

Another object is to provide a new and novel heat actuated power element.

Another object is to provide means for manually controlling the apparatus, and which means returns to inactive position upon resumption of the automatic means.

The invention consists in the improved construction and combination of parts, to be more vfully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying gdrawings, to be taken as a part of this speciiication, I have fully and clearly illustrated my invention, in which drawings- Figure 1 is a schematic view of the control' apparatus embodied in a heating system;v

Fig. 2is a view in side elevation of the'apparatus with parts broken away;

Fig. 3 is a view in top elevation of the apparatus with' the cover removed;

Fig.`4 is a view of aportion of the apparatus showing the method of connecting the lever members to the valve stem, and showing the manual operating means for the valve member;

Fig. 5 is a view substantially along the line 5-5 of Fig. 2 and` looking in the direction of the arrows;

Fig. 6 is a partial view substantially along the line 6 6 of Fig. 2 and looking in the direction of the arrows, and

Fig. 'l is a detailedview of holding means.

Referring to the drawings by characters of reference, the numeral I designates generally my control apparatus. The apparatus I comprises a lower chambered casing 2 having an open top wall 3 and having a hollow tubular strainer chamber 4 cast integral with its lower wall 5. The strainer chamber Ihas an inlet 6 Aat one end portion thereof and an outlet at its other end portion which' leads to the interior of .the stop member the casing 2. A valve mechanism 1, actuated by a oat lmeans 8, controls flow of fluid from the strainer chamber 4 to the casing 2 and acts to maintain a substantially constant predetermined liquid level within the chamber 4.v A hollow outlet boss 9 through the lower wall 5 has an outlet port I and a valve seat II and is internally threaded, as at I2, adjacent its exterior end to receive an outlet conduit I3 for flow of fluid to the fuel burner or burner vessel I4. Fluid ow through the port I0 is controlled by a valve member I which extends upwardly within the casing 2, through its top wall 3, and has a lower end portion comprising a seating part I6 and a V-shaped, flow controlling port I1 which cooperates with the outlet port Iii to control the rate of ow of liquid from the casing 2 to the burner I4. A cover member secured to the top of the casing 2 forms a cover therefor and an upwardly extending tubular wall 2| of the member 20 defines a chamber 22. The chamber v members 28, 29.

22 has its open top wall closedjby a cover memberV 23, which cover member 23 has a downwardly extending flange portion 2l for cooperation with the first cover member 20 to define a second chamber 25. A reduced diameter end portion 2l of the valve member I5 is` located in the chamber 22 and is guided for reciprocal movement in an apertured flange 21 extending inwardly into the chamber- 22 from a side wall 21. Rotation of the valve member I5 is prevented by a pin 21 which reciprocates in a slot 21 of an inwardly extending wall portion 21d of the side wall of the chamber' casing 2. The iiange 21 h as screwthreaded therein a pair of stop members 28, 2l which extend downwardly from the lower flange surface within the chamber 22 and substantially parallel to the valve member I5. The members 28, 29 have anges 30, 3i respectively which engage a protuberance 32-on the valve member II to limit its vertical reciprocal movement. ,Li-shaped, friction holding' member 22' is positioned adjacent the underface of the iiange 2.1 and 'has a pair of'threaded apertures, one in each leg, through which the members 28, 29 are y* threaded. The apertures in the legs `of the holding member 32* are'constructed and arranged so that when the member 32* is in its inert y state, the center lines of the apertures are slightly closer together than the centerlines of the For example, when the members 28, 29 haveI a :Fg-40 thread and are spaced about 1*.; of an inch, on centers, `the center line distance of the apertures in the member I2* in adjusted position.

A rod or fulcrum member 33 has its opposite ends secured within bosses 34, 35 which extend inwardly into the 'chamber 22 from a side wall 35 thereof, and `from the wall 21a. A lever member 38 comprises a pair of arms 39, 40 joined together at their top edge portions by a cross member 4|. The arms 39, 40 have aligned apertures therethrough which receive the rod 33 and pivotally support the lever member 38. The arm 39 has a circular portion 33B which is positioned intermediate the protuberance 32 and a shoulder 42 formed on the valve member l5, at the intersection of the upper end portion 20 and the full-sized stem portion of the member I5. As the lever member 38 is rotated clockwise (see Fig. 2) on the rod 33, the circular por.- tion 35 engages the protuberance 32 to vertically lift the valve member l5. The arm i0 extends on the opposite side of the rod 33 and toward an end wall 43 of the chamber 22 and is apertured to receive a pin 44 carried in a vertically reciprocal rod 45. The rod 45 is guided at its lower end within an aperture extending through an L-shaped supporting member having one leg .48 secured to wall 43 and the other leg 41 extending perpendicularly thereto, the leg 41 also serving as an abutment for the lower end of a helical coil compression spring 08.y The spring 48 has its upper end engaging and held under compression against the pin 44 and so that it acts to exert a force to urge the rod 45 in an upwardly direction. A second helical coil cpmpression spring 40 concentric with and surrounding rod 45 has its lower end portion abutting the pin 44 and has its upper end engaging the underside of the lower leg of a U-shaped member 50.

is moved into or out of circuit making position. Flexible lead wires 56, 51 connect the switch 55 to binding posts 50, 59 respectively of a terminal strip 50. The strip 80, which is made of a suitable electric insulating material, such as Bakelite, is supported within the chamber. 25 by a vertically extending portion 6| of a plate member 52- secured, as by screws, to the cover member 20.

The lever member arm i0 has an apertured or bifurcated portion 10 for reception of a lip 1| of a bimetallic power element 12. The spring 48 urges oneedge portion of the arm against the element 12 to prevent any lost motion between the arm 40 and the lip 1 I. The element 12, which operates under high-fire conditions, to be hereinafter described, comprises the lip 1i and a cylindrical portion 13. The portion 13 is not closed but has its side wall split longitudinally and the lip connected thereto so that the lip extends radially outward from the portion 13 adjacent the split. A plate member 13a is secured to and closes an aperture through the cover member 20 which connects the interior of the member 2 to the chamber 22. The member 13L1 has secured thereto, as by screws 13b, an L-shaped supporting member 13. The element 12 is secured adjacent the split of the portion 13 and on the opposite side thereoi'from the lip l12 by the supporting member 13G. The element 12 is heated by a suitable electrical heating unit 14 which is cylindrical in form and is positioned within and substantially fitting the interior ofthe portion 13. The heating unit 14 has its lead wires 15, 16 extending upward, one from each end of the unit 14,-toward the cover member 23 and connected to binding posts 11, 18 respectively. The posts 11, 18 are carried by a Bakelite terminal block 19. The block 19 is positioned for convenience The member has aligned apertures through the parallellegs which receive and are free to move along the axis of the pin 44. The member 50 is held in' adjusted position against the spring 4S by a. nut, adjustment member 5| threaded on the upper end of the rod 45. In .this manner the member 50 is held in any adjusted position relative to the pin 44 and yet, due to the expansive force exerted by the spring 49, the member 50 will move in response to movement of'the pin s4 by the'lever member .38.' Movement of the-pin 88 isv transmitted -to a horizontally extending shaft 52 by a second U-shaped member 53 having its parallel arms radially secured to and in alignment with the horizontal axis of the shaft 52. The members 50'and 53 therefore form a link connecting the rod l5 to the shaft 52 so that reciprocal movement of the rod is transmitted to the shaft as rotary movement.,v The shaft 52 having one end journaled in the end wall t3 extends centrally parallel to and between the side walls 36, 21, and has its otherend portionf'53 journaled in and extending through an opposite end wall 54 of the chamber 22. The en'd portion 53I extending beyond the wall 54 is positioned within the chamber 25 and carries a mercury tube switch 55 at right angles to the axis.

of the shaft 52"and is so positioned that upon rotation of the shaft 52 by the' rod 45 the switch just beneath the cover member 23 so that upon removal of the member 23 the binding posts 11, 18 will be in a convenient location for connection of lead wires 80, 8|'. The posts .'51, 18 are connected respectively to a pair of vertically aligned binding posts 83 carried by a Bakelite terminal strip 84 by the lead wires 80, 8|. The strip 84 is positioned external of the control apparatus and is carried by the wall 36. The block 19 also has a binding post 8,5, situated similarly to lthe posts 11, 18, which is connected by a lead wire 86 to a binding post 01 carried by the strip 84 adjacent posts 83. The block, 10 is carried by the upper horizontal leg 88 of a Z-shaped member 89 which has its lower horizontal leg 90 secured as by means of screws to the plate member 13a. Upon energization of the heating unit 1t the cylindrical portion 13 opens up, or unwinds, thereby moving the lip 1| which in turn rotates the lever member 38. Rotation of the lever member 38 rocks the switch 55 into circuit making position to start the air supplying means 9|.

A second bimetallic power element |00 for use under medium-fire operation is similar in con struction to the element 12 and has a split cylindrical portion |01 and a lip |02. The element |00 is actuated by a heating unit |03' similar to the unit 14 and similarly placed. Lead wires |04, |05 extend upward, one from each side 'of the unit |03, and are connected to the bindingl posts and 18 respectively. A second levermember |05 is similar to the lever member 38 and has a pair of arms |01, 108 and a cross member |09. The rod 33 extends through aligned apertures in the arms |01, |08 and pivotally supports the member 106 intermediate the arms 39, 40 and under the cross member 4|. The arm |01 extends from the rod toward the wall 00, substantially l parallel to the'arm 00, and has a rounded portion 21* so that it aligns with an adjustable stop member I|| and engages therewith upon upward movementof the portion I|0 thereby limiting vopening movement of the valve member I0. The

member III is screw-threadedly secured to a plate-like member I|2 secured, as by screws. to the ange 21 and to a flange ||0 extending in- -ward from the end wall 00. The other arm |00 of the lever member |00 is bifureated and extends toward the element |00 and receives the lip |02 between it s` bifurcated ends. Upon energization of the unit |00, the lip |02 acts to rock the lever member |00 in a manner similar to the rocking of the lever member 00 by the lip 1|.

of the electrical energy supply by enabling the operator to utilize the burner to a limited extent.

The mechanism |20 comprises a rod-like plunger member |20 carried within aligned apertures,

one being inthe boss 21 projecting inward into the chamber 22 and the other being in the plate member The rod-like member |20 has rigidly secured thereto a cam member which is cooperable with a pin |20 rigid .with and carried by the valve member I0. Upon rotation of the mem- |20 until it reaches and falls into a notch IOI. The cam end |02 at the time the pin.|20 reaches the notch |0I engages the side wall 21 to prevent movement of the cam member |20 beyond the desired position for manually vcontrolled flow.- A helical coil spring |00 is arranged concentrically with and surrounds the plunger memberv |20 and normally urges the cam member |20 in a counter-clockwise direction (see Fig. 3). Spring |00 has one end |00 bent downward at right angles to the plane of the lower end ofthe spring |00 and extends into an aperture in the cam member |20. The upper end |00 of the spring |00 en- Eages the side wall 21 and the underface of the ange 21 so that the spring |00 is held under compression and winding stress, which tends to rotate the cam member |20 in a counterclockwise direction (see Fig. 3). The holding force due to the downward thrust of the valve member I0 holding pin |20 in the notch |0I is suiilclent however to hold the cam member |20 and vplunger member |20 against rotation by the spring |00 after manual operation of the mechanism |20.

However, in the event the electrical energy supply is reestablished and the valve member |0 is` moved by either of the power elements -12 or |00, the valve member I0 will have movedto a further open position and the' pin |20 moved out of the notch |0I so that the cam member |20rotates, under the winding stress of the spring |00, into the normal ineffective position out of the path of movement of pin |20, and the valve member I0` again is solely controlled by the power elements 12 or |00. Upon a subsequent power failure, the operation of the apparatus by the manually operable mechanism |20 will require a new manual' movement of the mechanism |20. The rod-like plunger member |20 has at its upper end, screw-threadedly secured thereto, an adjustment nut |00 whichle'xtends above the cover member 20 and serves as a convenient means for rotating the plunger member |20. ,The nut |00 has its lower end portion bearing against the upper surface of the flange 21 and limits downward movement of the plunger member |20 caused by the weight of the valve member v ber m in s clockwise direction (see rias) the pin |20 rides along thecam surface |00 of member I0 acting through the pin |20 and the cam member |20, and alsothe force exerted by the spring |00 acting to expand to its normal length. The nut' |00 by its screw-threaded relation with the plunger member |20 acts to determine the vertical position of the member |20 and the connected cam member |20 so thatfthe opening movement of the valve member I0 by the cam surface |00 may be set for any predetermined fuel now. After adjustment, the nut |00 is held rigid with the plunger member |20 as by a drop of solder, or any other known means for preventing a nut from rotating relative to the rod on which it is screw-threaded.

`The apparatus is preferably connected into a heating apparatus, as shown in Fig. l. The control apparatus I is diagrammatically shown vand the respective parts are designated by characters of reference corresponding to the parts shown in the other figures of the drawings. Electrical energy is supplied from a suitable source of supply through lead wires |00, I0| to the primary coil |02 of a transformer |00. One side of the transformer secondary |00 is connected by a lead wire |00 to thel movable bimetallic element |00 of a room thermostat |01. .The element |00 carries two contact members |00, |00 cooperable respectively with stationary contact members |00, |0|, the contact members |00, |00 engaging at a predetermined temperature of element |00, and upon a lower predetermined temperature of element |00 the contact members |00, I0| are operable to engage. `Engagement of contact members |00, |00 closes a circuit from 'the transformer secondary |04, through lead wire |00, element |00, contact members |00, |00, lead wire |02 connected to lead wire 10, heating unit |00, 'v lead wire 10, and a lead wire |00 to the other side of the secondary |00. Upon energization of the unit |00, heat begins to flow to the cylindrical portion I 0I of the power element |00 and the lip |02 acts to rotate the lever member |00 to lift the valve member I0 until the arm |01 engages the stop member III. The oil or other l fluid fuel will now flow from outlet 0 through conduit |0.to the burner I0, positioned within a furnace |00 or other heat transfer means, and the fuel is burned thereinunder natural draft conditions. 'Ihe products of combustion pass through the stack |00 to atmosphere and the .heat passes through pipe means |00 to the enclosed space in which the thermostat |01. is located. Should thetemperature surrounding the thermostat |01 fall to a predetermined lower temperature, the element I 00 will have moved to cause contact members |09, IGI to engage thereby completing an electrical circuit from the secondary |00, through lead wire |00, element |00, contact members |09, |0I, a lead wire |10 connected to lead wire |00, and therethrough to energize the heating unit 10. From unit 10 the current flows through lead wire |00 and lead wire |00 to the other side of the secondary |00. Upon energization of the heating unit 14 the valve member I5 until the protuberance 32 engagesy the nangesl of the maximum orhigh-re stopxnember 29. At the same time the lever member 38 moves the rod 45 downward thereby,l

through the linkage, rotating the tube switch 55 into closed circuit position. f Closing ofthe switchv 55 energizes the air supplying means 9| which supplies the necessary air for combustionv of the high-firevfuel iiow tothe burner I4. The circuit is from a source of supply through a lead Wire |10, switch 55, a lead wire |11, air supplying means 9|, and a lead wire I18back to the source. The time of closing of the switch 55 relative to the positioning of the valve member I5 is controlled or adjusted by means of the nut member v'Ihe operation of my apparatus is as follows: With the thermostat |51 in the position as shown in Fig. 1, the temperature of the room heated by the furnace |64, and in which the thermostat.

|51 is located, will be at or above a predetermined temperature. In this position the fuel controlling apparatus I will be substantially as shown in Fig. 2, and as diagrammaticallyfshown in Fig. 1. The valve member I5 in this position isheld partially open by the engagement ofthe v protuberance 32 with theiiange 30 of the lowfire stop member 28. Fuel is therefore being supplied from theoutlet 9 through conduit I3 to the burner I4 for maintaining the pilot or low-fire operation of the furnace. This pilot nre operation ofthe burner I4 is intended .to maintain a flame at all times in the burner I4 but not to supply suicient heat t-o the room heated by the furnace |64 to maintain the room at the desired temperature in any but the very mildest weather. Upon decrease in temperature of the room, the thermostat |51 Will move so that the contact members |50, |50 Vwill engage and energize the power element |00. Energization of the power element acts to rotate the lever member |06 into engagement with the medium-re stop member II| and to lift the valve .member I a predetermined amount so that oil` is supplied through the conduit i3 to the burner I0v at a higher rate of ow. This medium-nre voperation of the burner Iii may be Such that the fuel which is supplied thereto is the maximum amount which the. burner It will burn without the addition of supplementary or forced air.

The furnace IM under medium-hre operation is supplying a greater quantity of heat to the room, and which under moderate outside temperature conditions will be suilcient to maintain the room at least at thepredetermined temperature.,

Should the heat supplied by the burner I4, operating under medium-nre conditions, not be suiilcient to maintain the room temperature at the desired predetermined temperature andthe assume and rod I5 to rotate the shaft 52, and thereby the tube switch 55, into circuit making position so that A additional air is supplied, by means of the air supplying means 9 I, to the burner Il. Upon increase in temperature of the'room, thel thermostat |51 acts nrst to open the contact members |59, ISI,v tovdeenergize the power element 12. Subsequent to deenergization, the

. power element 12 will cool and allow the valve' room temperature falls a. predetermined amount Y below this first predetermined temperature, then the element |56 of the thermostat |51 will move the contact members |59, IBI into engagement and the contact members |59, I IGI will act to energize the power element l2.` UponV energization 'of the power element 12 the lever. member` 38 `is rotated to lift the valve member l5 Vin a furtherv open direction and until the protuherance 32 engages the underside of the ange 3| of y 'the high-nre' stop member 29. Subsequent to movement of the valve member I5 by the power Y element 12, but prior to the engagement of the protuberance 32 with the ange 3|; the. lever member 38 will have acted through the pin M `ber III. justed so that the switch 55 will not open the circuit between the lead wires I16-.QI 1d |11 to. deenergizev the air supplying means SI until the lever member 38 has moved away from the protuberance 32 toward the shoulder 42 and which movement occurs upon continued cooling of the power element l12. Upon a further increase in temperature of the room the thermostat |51 will act to open the contact members |58, |60 to deenergize the power element |00 so that the yvalve member I5 will move toward closed position and into engagement with the stop member 28 so that the flow of fuel is again such as to supply a low -or pilot-fire operation of the burner i4.

I t maybe seen that I have provided a fluid fuel controlling system in which I-can independ-V ently adjust the now of fuel for three diierent` burner operations, and that I have provided automatic means for regulating the flow of fuel to the burner so that the room or other enclosed spaced heated thereby will be maintained within a predetermined 'desired temperature range. I have also provided a novel and' simple means for adjusting the energization of the supplementary air supplying means so that additional air may be supplied to the burner at any given position of the fuel valve.

What I claim and desire'to secure by Letters .by such continued movement of said lever, and

means including a switch operable to reduce the air supply for the apparatus and actuated by said shaft rotation.

2. A control device fory liquid fuel burning apparatus comprising a fuel metering valve, means to limit movement of, said valve toward closed position, a lever engageable'with and operable to control movement of said valve toward closed position, said lever having a lost-motion connection with said valve, a shaft rotatable by said lever subsequent to limitation of'movement of saidV valve, means including a switch operable to reduce the air supply f or the apparatus and actuated by said shaft rotation, and automatic means to move said limiting means so that saidvalve can be moved further toward closed position.

3. In a control device, a valve for controlling the supply of fuel to a burner,.a lever having a range of movement and having a lost-motion connection with said valve,' means to limit movement of said valve within the range of movement of said lever, meansincluding a. switch for con-- trolling thsupply of air to thel burner and operable by said lever, and means determining the extent of movement of said lever subsequent to limitation of movement of said valve requisite to operate said switch. 4. A control device for the burner of a heating apparatus comprising, a valve operable to control the supply ofiuei to the burner, abutment meansV on said valve, means holding said valve in an open position to supply fuel for a pilot name, a lever engageable with said abutment means to move said valve further towardl open position, means engageable with said lever to limit opening movement o`f said valve, a second lever engageable with said abutment means to move said valve beyond said limit of movement, and means determining the extent of opening movement of said valve by said second lever. v

5. In a control system for a heating apparatus having a burner, a valve controlling`the supply of fuel to the burner, abutment means on said valve, means engageable with said abutment means and holding said valve in an open position to supply fuel for a pilot llame, a lever engage-V able with said abutment means to move saidvalve further toward openposition, means engageable with said lever to limit opening move- Y ment of said valve to provide a predeterminedlimited tuel supply, a second lever engageable with said abutment means to move said' valve beyond said limit of movement, a motor driven fan to supply air to the burner, a switch con trolling the motor of said fan and operable' by said second lever, and means determining the extent of opening movement of said valve by said second lever.

6. In a control system for a heating apparatus having'a burner, a valve controlling the supply of fuel to the burma-means holding said valve in an open position to` supply, fuel for a pilot flame, abutment means on said valve, a lever temperature and having a second switch closed' upon temperature decrease below said predetermined temperature, an electrically energized heat motor controlled by said rst switch, a lever moved by said heat motor, a valve for controlling the supply of fuel to the burner and operable by said lever for movement thereby toward open po.

' sition, a stop member engageabie by said lever to means to limit the maximum opening movement limit opening movement of said valve, an electrically energized heat motor controlled by said second switch, a lever moved by said second-named heat motor and cooperable with said valve to move said valve further toward open position,

of said valve, a motor driven fan for supplying air vto the burner, and a switch controlled by said second-named heat motor and controlling the circuit of said fan.

9. In a control device, a housing member having a base portion, a pair of spaced supporting armslocated within said housing member and secured to said base portion, a bimetallic heat actuated power element having a substantially cylindrical portion with spaced longitudinal-edge portionseand a lip portion extending from said cylindrical portion adjacent one of said edge portions, the other of said edge portions being secured to one of said arms, said cylindrical portion being operable upon being heated to move said one edge portion relative to said other edge portion thereby to move said lip portion, aresist-` engageable with said abutment means to move l said valve further toward open position, means engageable with said lever to limit opening move ment of said valve to provide a predetermined limited fuel supply, a secondlever engageable with said abutment means to move said'valve beyond said limit of movement, la motor drivenV ian to supplyl air to the burner, a switch controlling the motor of said fan and operable by said second lever, means determining the extent of movement oi said second lever requisite to operate said switch, and means determining the extent of opening movement of said valve by said second lever. Y

'7. vIn a control system for a heating apparatus having a burner, a thermostat having a nrst' ance member for heating said cylindrical portion and positioned within said cylindrical portion, said resistance member having a lead wire. a terminal member having a lead wire terminal and carried by the other of said pair of arms and overlying said power element, said lead wire being connected to said terminal, a shaft member rotatably carried by said housing member and extending intermediate said onev arm and said terminal member and being substantially parallel to said base portion, a lever mechanism operably connecting said shaft member and said power element lip portion and Jbeing operable upon movement by said power element to rotate said shaft member, anda mercury tube switch means carried by 'said shaft member, said switch means being operable to control an electrical circuit upon rotation of said shaft member.

10. In -a control device, a supporting member. a lever member fulcrumed on said supporting member and having a pair of substantially .parallel arm members, a supporting arm carried by said supporting member, a bimetallic heat actuated able by said second-named heat motor and engageable with said valve to move said valve further toward open position, and means to limit the 'maximum' opening movement of said valve.

8. In a control system for a heating apparatus having a-burner, a thermostat having a first switch closed upon occurrence oi a predetermined power element having a substantially cylindrical l'portion with spaced longitudinal-edge portions substantially facing each other and a lip portion extending from one of said edge portions, the other of said edge portions being secured to said supporting arm, said cylindrical portion being operable upon being heated to move said one edge portion relative to said other edge portionthereby to move said lip portion, said lip portion being operable upon movement to engage one o! said arm members and to move said lever member, a valve member having an abutment spaced from and engageable by the other of said arm members, said power, element being operable to move said other arm member into engagement with said abutment and to pick up and to move l said valve member in opening direction,l and an adjustable stop member carried by said supporting member, said other arm member having an extending portion engageable with said stop member to limit movement of said valve member by said lever member in opening direction, said other arm member being freely movable away from said abutment upon limitation of closing movement of said valve member.

11. In a control devices, heat motor, a lever 'operable by said heat motor, a controlling means a longitudinally movable member, an abutment on said movable member engageable by said second-named lever, resilient means continually urging said abutment into engagementwith said second-named lever. -an abutment member carried by said movable member, means adjustably positioning said abutment member longitudinally relative to said movable member, means engagecontrolling means in said one direction, a switch,

able with said abutment member and operable upon movement oi said movable member for controlling the operation of said switch, and means continually urging said last-named means into engagement with said abutment member.

12. I n a control device, a control means, a rotary member operatively connected to and for actuating said means, a lever arm extending from and operable to rotate said member, alongitudinally reciprocal thrust member, means to guide the movement of said thrust member, an abutment member slidable on said thrust member. and

. operatively connected to said arm, a spring interposed between said thrust member and said abutment member,a power element having a position of rest and movable therefrom to actuate said control means, means operatively connecting said powerelement to said thrust member, and an adjustment member carried by said thrust member and operable to position said abutment-member .against the force of said spring and relative to said power element position oi'- rest thereby to determine the operation. of said control meansby said power element.

13. In a control device for actuating an electric switch, a supporting member, a pair of spaced supporting arms extending from said member, an

`connecting said shaft Amember and said power element and being operable upon movement by said power element to rotate said shaft member,

and a switch means operable by rotation of said shaft member.

14. In a control device. a housing member'having a base portion, bracket means carried by said base portion and having a pair oi spaced supporting arms located lwithin saidfhousing member, a bimetallicA power elementY carried by one of said pair of arms, a resistance member for heating said element, ame'mber having a plu-V rality of Vterminals-carried by the otherof said pair of arms-and overlying said one arm. lead carried by said base portion, 9, second bimetallic power element carried by said second bracket means, a second resistance member for heating said second power element, lead wires connecting said scond resistance member to certain of said terminals, a rst lever member pivotally supported on said housing member and operable to be moved by said iirst-named element, a second lever member pivotally supported on said housing member adjacent said first-named lever member and operable to be moved by said secondnamed element, a valve member carried in said housing member and having an abutment, means on said rst and said second lever member operable to engage said abutment so that each 'of said lever members is operable upon energization of the respective power elements by the respective resistance members to move said valve meml ber in one direction, stop means carried by said housing member to limit movement oi said valve member` in said one direction, and stop means carried by said housing -member and engageable by said abutment to limit movement ofsaid valve member by said second lever member in said one direction.

l5. In a control device, an automatically operable valve having a longitudinally slidable stem, a manually rotatable operating rod extending longitudinally of and closely adjacent said stem, said stem having an abutment rigid therewith and providing a downward-facing' bearing surface, a cam member secured to and ,partially surrounding said rod and having an upper cam surface engageable with said abutment to lift said valve upon rotation of said rod, means on said cam member cooperable with said abutment to hold said rod in rotated valve lifting position, auto- Y ment member against said supporting member. and to rotate said .rod upon opening movement wiresv connecting said resistance member to cerof :au a second bracket meats ,75

matic means operable to lift said valve to disengage said abutment from said cam means, and

means to rotate said rod to move said cam member out of rotated valve vlifting position upon liftoperable upon rotation of said rod to open and hold open said valve, means to adjust said rod longitudinally to regulate the opening of said valve byfsaid cam means upon rotation of said rod, automatic means to open said valve, and means voperable upon opening of said valve by said automatic means to render said cam means ineffective to hold open said valve.

1'7, In acontrol device, an automatically operable valve having a longitudinally slidable stem,

a supporting member having a bearing aperture therethrough extending parallel to said stem,

a manual operating rod reciprocable and rotatable in said aperture. cooperable cam means on said rod and 4said stem operable upon rotation .of said rod-to open andhold open said valve, an

abutment member longitudinally adjustable on said rod and engageablewith .said supportingA of said valve by said automatic means, thereby to render said cam means ineffective to hold open Vsaidvalve.V

a supporting bracket carried by said supporting member, a bimetallic heat actuated power element bent to providea substantially cylindrical body portion with laterally spaced longitudinal edge portions and with an operating arm extending outward from one of said edge portions, said body portion having all of its length continuously curved from one to the other of said edge portions, means rigidly securing the other of said edge portions to said bracket, said lever member having an end slot providing spaced abutments embracing said operating arm, an electric resistance heater surrounded by said body portion, and control means operable by said lever member.

19. Ina control device, a casing, a horizontal supporting shaft secured in said casing, a lever member journaled on said shaft and having an arm with a horizontal end slot, an upstanding bracket having a base portion secured to the base of said casing, a bimetallic heat actuated power element bent to provide a substantially cylindrical body portion with laterally spaced longitudinal edge portions substantially facing each other and with an operating arm extending horizontally from one of said edge portions into said end slot to move said lever member, means rigidly securing the other of said edge portions to said bracket, an electrical resistance heating element positioned within said cylindrical body portion, and control means operable by said lever member.

20. In a control device, a casing, a horizontally pivoted lever member having an arm with an end slot and supported in'saidcasing, an upstanding bracket having a base portion, a second upstanding bracket having a base portion and a horizontal flange over-hanging said first bracket, means securing said base portions together and to the base of said casing, a bimetallic heat'actuated power element bent to provide a substantially cylindrical body portion with laterally spaced longitudinal edge portions and with an operating arm extending from one of said edge portions into said slot to move said lever member, means rigidly securing the other of saidedge portions to said mst-named bracket, a terminal block carried by said ilange, an electric resist .ance heater positioned within said cylindrical y body portion, leadA wires extending from said heater and secured to said block, and control meansoperable by said lever member.

2l. A control device for liquid fuel burning apparatus comprising a fuel metering valve, automatic means for moving said valve partially toward open position, automatic means for continuing the movement of said valve toward open position, and means operable by said secondynamed `automatic means subsequent to initiasaid air supply means being so connected and related to said second-named automatic means that said air supply means is actuated to increase the air supply to the apparatus subsequent to initiation of said second stage opening movement and is actuated to decrease the air supply to the apparatus subsequent to said second stage closing movement.

23. In automatically controling oil burning apparatus of the type having a burner vessel and means for conducting liquid fuel thereto, valve means for controlling the iiow of fuel to said 'burner vessel comprising a casing, a valve memyber disposed in said casingvior movement between open and closed positions, a pair of valve actuating lever elements engaging said valve member to impart opening movement thereto, means in said casing for limiting the degree of movement of one of said lever elements toward a valve opening position, and thermo-responsive means engaging said lever elements and imparting movement thereto.

24. In automatically controlled oil burning apparatus of the type having a burner vessel and lmeans for conducting liquid fuel thereto, valve means for controlling the flow of fuel to said burner vessel comprising a casing, a valve member disposed in said casing for movement between open and closed positions, a pair of valve actuating lever elements engaging said valve member to impart opening movement thereto, means in said casing for limiting the degree of movement of one of said lever elements toward a valve opening position, thermo-responsive means engaging said lever elements, and electric resistance coils ,disposed adjacent said thermo-responsive means,

the introduction of electric current to said resistance coils serving to heat said thermo-respom sive means to cause movement of said lever elements and said valve member.

WAL'I'ER S. LANDON. 

